Device for expelling static charges from dielectrical substances



June 21, 1949. H. R. JOHNSON DEVICE FOR EXPELLING STATIC CHARGE FROMDIELECTRICAL SUBSTANCES Flled Feb 24 1948 Howard R. Johnson INVENTOR.

Patented June 21, 1949 UNITED STATES PATENT OFFICE DEVICE FOR EXPELLINGSTATIC CHARGES FROM DIELECTBICAL SUBSTANCES Howard B. Johnson,Baltimore, Md.

Application February 24, 1948, Serial No. 10,538

4 Claims. (Cl. 271-18) This invention relates to new and usefulimprovements in attachments for mimeograph machines, and the primaryobject of the present invention is to provide a device for expellingstatic charges from di-electrical substances such as a stack of paperwhich is disposed upon a mimeograph machine.

Another important object of the present invention is to provide anattachment for mimeograph machines adjustable relative to a stack ofpaper on the machine for creating a magnetic field between theattachment and stack of paper which will facilitate a single sheet ofpaper to be discharged from the stack to the roller drum of the machine.I

A further object of the present invention is to provide a device of theaforementioned character that is quickly and readily applied to orremoved from a mimeograph machine or a sheet separating machine in aconvenient manner for use in conjunction with stacks of di-electricalsubstances of various sizes.

A still further aim of the present invention is to provide a device forexpelling static charges from di-electrical substances that is simpleand practical in construction, strong and reliable in use, small andcompact in structure, relatively inexpensive to manufacture, andotherwise well adapted for the purposes for which the same is intended.

Other objects and advantages reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming part hereof, wherein likenumerals refer to like parts throughout, and in which:

Figure 1 is a perspective view of a conventional mimeograph machine, andshowing the present invention applied thereto in use;

Figure 2 is an elevational view of the present invention removed fromthe mimeograph machine; and,

Figure 3 is a longitudinal horizontal sectional view taken substantiallyon the plane of section line 3-3 of Figure 2.

Referring now to the drawings in detail, wherein for the purpose ofillustration, there is disclosed a preferred embodiment of the presentinvention, the numeral l represents a conventional mimeograph machinegenerally, comprising a working table [2 having a side wall i4.

Fixed on the table I2, is a support bracket l6 that slidably andadjustably supports a retainer arm I8 on which there are providedadjustable paper engaging pads 26.

The present invention does not attempt to claim the above conventionalstructure but is merely an attachment that is to be used in conjunctionwith the same.

The numeral 22 represents the present invention generally, comprising asubstantially rectangular, preferably plastic housing 24 having acentral, transverse, substantially cylindrical recess 26 thatfrictionally engages a field coil 28 that is connected by conductivewires 30, in a conventional manner, to a usual step-down transformer 32.It should be noted, that one end 34 of the field coil core 38 is flushwith the inner face 38 of the housing 24 for a purpose which will laterbe more fully apparent.

Opposite the ends 40 and 42 of the housing 24, is a pair ofsubstantially rectangular metal plates 44 and 46 to the outer faces ofwhich are suitably fixed resilient cushions or pads 48 and 60. Rigidlysecured to the inner faces of the metal plates 44 and 46, is a pluralityof support arms or rods 52 that slidably engage longitudinal guideopenings 54 formed in the ends 40 and 42 of the housing 24. Set screws66 adjustably carried by the outer face 58 of the housing 24 areadjustable to frictionally engage one support arm 62 for each of theplates 44 and 46, to selectively position the plates 44 and 46 relativeto the ends 48 and 42 of the housing 24.

Recessed in the inner face 28 of the housing 24, adjacent the end 34 ofthe field core 36, is

a pair of resilient support lugs 68 and 62 having ends 64 and 66 thatproject outwardly from the inner face 38 of the housing, as best shownin Figure 3 of the drawings.

The numeral 68 represents a substantially diamond shaped vibrator plateor diaphragm of relatively thin material having rounded end corners 10and 12 that oppose the ends 64 and 66 of the lugs 66 and 62, a roundedupper corner 14 that is disposed in a plane below the upper face 16 ofthe housing 24, and a lower rounded corner 18 that is disposed in aplane above the lower face 86 of the housing 24. Counter-sunken screwsor the like 82 and 84 extend through the rounded end corners ill and 12of the vibrator plate 68 and receivably engage suitable aperturesprovided in the outer ends 64 and 66 of the lugs and 62 to retain thevibrator plate 68 spaced relative to the inner face 38 of the housing24, and the central portion of the vibrator plate 68 in opposition tothe end 34 of the field coil core 36.

In practical use of the present invention, a stack of paper 66 isdisposed on the table l2 so that one side edge of the stack frictionallyengages the side wall I4, and the remaining side edge of the stackfrictionally engages the pads 28.

,The plates 44 and 46 are then adjusted so that the pads 48 and 58frictionally engage the side wall I4 and retainer arm 18 respectively tohold the housing fixed to the machine In with the lower face 80 of thehousing frictionally engaging the table l2. In this position, thevibrator plate 88 frictionally engages the free edges of the stack 88that are disposed away from the roller drum 88 of the machine l0.

Frequently during the operation of a mimeograph machine, such as thatshown in Figure 1 and represented by the numeral [8, as the paper feederarm 98 is actuated by a suitable mechanism (not shown) to eilect adischarge of a single sheet of material from the stack 86, staticcharges between the sheets of paper in the stack 88 will prevent asingle sheet from being ejected to the roller 88, thus preventing theprinted matter from being conveniently placed upon the sheet which isdisposed between the roller and print holding plate (not shown). It is,therefore, the primary feature of this invention to provide anattachment for mimeograph machines or other such machines whichdischarge sheets of paper from a stack, that will reduce this staticcharge between sheets of paper so that a single sheet of paper may bedischarged from the stack in a convenient manner. When the field coil 36is energized by a pulsating or alternating electric current passingthrough the transformer 32 and conductive wires 30, a pulsatingelectromagnetic field will exist to affect a vibration of the vibratorplate 63 and the said vibrator plate will engage the edges of thestack88 to effect and act upon the normal static charges between sheets ofpaper in the stack 68. It has been found that as the vibrator plateengages the edges of the stack of paper or other such di-electricalsubstances, the attraction between adjacent sheets of paper will be lessso that a single sheet of paper may be removed from the stack in aconvenient manner.

In view of the foregoing description taken in conjunction with theaccompanying drawings it is believed that a clear understanding of thedevice will be quite apparent to those skilled in this art. A moredetailed description is accordingly deemed unnecessary.

It is to be understood, however, that even though there is herein shownand described a preferred embodiment of the invention the same issusceptible to certain changes fully comprehended by the spirit of theinvention as herein described and the scope of the appended claims.

Having described the invention, what is claimed as new is:

1. The method of separating a single sheet of di-electrical substancesfrom a pile thereof comprising, the step of creating a pulsatingelectromagnetic field adjacent a pile of di-electricai substances foraffecting the static charges between the sheets thereof, and then thestep of removing a single sheet from the pile.

2. The method of separating a single sheet of di-electrical substancesfrom a pile thereof comprising, the step of creating a pulsatingelectromagnetic field adiacent a pile of di-electrical substances foraffecting the static charges between the sheets thereof, the step ofagitating the edges of the sheets of di-electrical substances in thepile, and then the step of removing a single sheet from the pile.

3. An attachment for mimeograph machines comprising a housing, means foradjustably mounting the housing on the bed of a mimeograph machine, andmeans for creating a pulsating electromagnetic field between the housingand a stack of di-electrical substances on the bed of the mimeographmachine for affecting static charges between a stack of di-electricalsubstances.

4. The combination of claim 3 wherein said last mentioned means includesa field coil operatively connected to a source of pulsating electriccurrent.

HOWARD R. JOHNSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 341,788 Arnold May 11, 18861,710,706 Maxner Apr. 30, 1929 1,716,602 Ross June 11, 1929 1,731,030Thompson Oct. 8, 1929 2,094,787 Flint Oct. 5, 1937 2,257,688 Jones Sept.30, 1941 2,300,923 Hornor Nov. 3, 1942

